Elevator



(No Model.) v

R. 0. SMITH.

' ELBYATOR.

No. 601,909. Patented Apr. 5,1898.

WITNESSES lNVENTOf? W, 61mm, 6 f rwas uonals PETERS 0o. PMOTMITMQ,WASHINGTON, o. c

ing a safety stop-clamp thereon and the car NITED STATES I RUDOLPH 0.SMITH, OF YONKERS, NEW YORK, ASSIGNOR'OF ONE-HALF TO JAMES CRUIGKSHANK,OF KINGSTON, NEW YORK.

ELEVATOR.

SPECIFICATION forming part of Letters Patent No. 601,909, dated April 5,1898.

Application filed October 19 1897.

To all whom it may concern.-

Be it known that I, RUDOLPH 0. SMITH, a citizen of the United States ofAmerica, and a resident of Yonkers, Westchester county, New York, haveinvented a new and useful Improvement in Elevators, of which thefollowing is a specification.

The invention relates to improvements in elevators; and it consists in anovel safety appliance to mitigate or avoid the consequences resultingfrom a fall or runaway of an elevator-car.

I present the invention in this application as embodied, forillustration, in an elevator comprising the usual car and shaft, thelatter being provided with suspended slideways havbeing provided with aprojection or dog normally in the vertical plane of said stop, butcapable of being removed therefrom at a definite point in the'line oftravel of the car in order that the dog may, when desired, pass saidstop without touching the same. The shaft is provided with a bar-railadapted to retain the dog in the vertical plane of said stop and t adefinite point in the line of the travel of the car to permit theattendant to withdraw the end of the dog from the vertical plane of saidstop in order that said dog may pass free of the stop. The slidewaysupon which the stop-clamps are placed are preferably of wood and have anincreased diameter below the normal position of the stops, and thesestops are preferably in the form of closed clamps encompassingtransversely the slideways and do not move on the latter except when theweight of the car is brought upon them, at which time the saidstop-clamps will by the weight of the car and its contentsbe drivendownward on theslideways and will scrape and out into the latter, so asto arrest the car by a constant retarding resistance, which will producea uniformly decreasing motion in the car until the latter comes to astandstill.

The invention will be more fully understood by reference to theaccompanying drawings, in which- Figure 1 is a vertical section of anelevatorshaft, showing the car connected to a hoist- Serial No. 655,722.(No model.)

ing-gear, the car and shaft being provided tion; and Fig. 3 is anenlarged side elevation of one of the dogs, shown in its relation to thestop-clamps and slideways. This figure also shows an enlarged top viewof a portion of one of the clamps or stops.

In the drawings the numeral 1 indicates a car, and 2 the customaryguide-rails secured to the guide-posts 3.

The car 1' is suspended by means of a suitable hoisting rope or cable,4, which passes over the sheaves 5 to any suitable hoisting apparatus6. The car will be provided with any of the usual forms ofcontrol-hand-rope, lever, or electrical connectionsfor stopping,starting, and'controlling the same.

The car is provided with a hand-lever 7, which has its fulcrum at 8 in astand 9, secured to the bottom of the car, and the lower end of thelever 7 passes through the bottom of the car with sufficient clearancefor operation. Underneath the floor of the car is pivotally mounted athree-armed lever, the arm 12 of which is by means of the rod 10connected with the lower end of the lever 7, while the arms 13 13 ofsaid three-armed 1ever are by means of links connected with the dogs 1414, which are adapted to slide in the inclosing casings 15 15 under theaction of said three-armed lever. The casings 15 are secured to thebottom of the car and support the dogs 14. The movement in one directionof the three-armed lever will set the dogs 14 in their normal runningposition, which is that illustrated in Fig. 3, and the movement of saidthree-armed lever in the opposite direction will withdraw the dogs 14inward, so that they will pass clear of the safety stops or clampshereinafter referred to. The dogs 14 and the three-armed lever withwhich they are connected may be directly operated by the attendant inthe car through the medium of the lever 7.

Extending lengthwise of the elevator-shaft is the bar or rail 20, andthe upper end of the lever '7 carries a pin or shaft 18, upon which isplaced a roller 19 for engagement with said bar or rail 20 during all ofthe travel of the car above the point at which the safety-stopappliances are intended to operate, and suitably adjacent to this pointthe bar or rail 20 is provided with the outward curve 21 for the purposeof permitting the outward movement of said lever 7 and the consequentinward movement of the dogs 14, whereby the said dogs may be permittedto escape contact with the stops or clamps to be hereinafter referredto. The dogs 14, as above described, are normally in their outwardposition (shown in Fig. 3) and always remain in this position, exceptwhen the upperend of the lever 7 is moved into the outward curve 21 ofthe bar or rail 20. The straight portion of the bar or rail 20, by itscontact with the upper end of the lever 7, imperatively maintains thedogs 14 in their outward position, and the attendant in the elevator,upon arriving at the outward curve 21 of said bar or rail, must move theupper end of the lever 7 outward into said curve 21 if he would preventthe dogs 14 from engaging the stop-clamps and arresting the car. Thedogs 14 have their outer ends hook-shaped to securely engage thestopclamps when meeting the latter upon the descent of the car, and theouter surfaces of the ends of the dogs 14 are tapered downward andoutward on a slanting line, so that said ends may not pass intooperative engagement with the stop -clamps during the ascent of the car.

The slideways are preferably of wood and are indicated by the numeral17, in the present instance two slideways being provided at one side ofthe elevator-shaft and two slideways at the other side of said shaft.The slideways 17 are secured at their upper part to the side of theelevator-shaft, and hence said slideways are in a suspended conditionand have their lower portions free to afiord a retarding slide to thestop-clamps 16, which are applied upon the upper portion of saidslideways. The stop-clamps 16 encompass the upper portions of theslideways 17, where said slideways are of slightly less cross-sectionthan below said stop-clamps, whereby a shoulder 30 on the slideways isformed and maintains the stop-clamps in a normally stationary position.In the present instance I have formed each of the stop-clamps 16 toengage two of the slideways 17, and, as indicated in the drawings, thedogs 14 protrude outward on a vertical line extending between theslideways 17 in position to engage the central portions of thestop-clamps 16. The inner surfaces of the stop-clamps 16 are preferablyserrated, as indicated in Fig. 3, in order that they may engage and cutinto the slideways 17 in case of accident.

The accompanying drawings illustrate the slideways 17 as suspended nearthe lower portion of the elevator-shaft, and it is my purpose to employslideways 17, which shall be about one-fifth of the entire height of theelevator-shaft, in order that the stop-clamps may be normally located atabout one-fifth of the rise of the car, since this arrangement andconstruction will give a safety sliding distance for a gradual stop incase of an emergency.

During the ordinary travel of the car the safety-dogs 14 are in theiroutward or extended position (shown in Fig. 3) in order that in case ofan accident resulting in the fall of the car the outer ends of said dogsmay be in position to engage said stop-clamps 16. Then during the usualemployment of the car the latter is approaching the outward curve 21 ofthe car or rail 20, it will be the duty of the attendant to push theupper end of the lever 7 outward into said curve in order that the dogs14 may be withdrawn inward and pass free of the stop-clamps 16. Theoutward curve 21 is of such predetermined length that there will not betime enough for the upper end of the lever 7 to enter the same wheneverthe speed of the car exceeds a fixed limit, and thus in case of a fallof the car the upper end of the lever 7 will not enter the outward curve21 of the rail 20, and the dogs 14 will, as a consequence, remain intheir outward position and engage the stop-clamps 16. In the event of anaccident and the fall of the car the dogs 14 will engage the stop-clamps16 and drive the latter downward upon the slideways 17, the serrationsof the stop-clamps abradin g or cutting into the slideways, whereby thecar will be stopped with a uniform and even resistance and not suddenly.The slideways 17 are preferably of wood, since this material offers auniform resistance; but they may be of other material and of any desiredshape. When the weight of the car is brought upon the stop-clamps, thelatter move downward upon the slideways 17 and thereby a uniformlydecreasing motion of the elevator-car until the latter comes to astandstill is secured.

The form of the shoulder 30 on the slideway 17 is not of materialconsequence, since whatever be the form of the slideway 17 the object isthat the stop-clamps shall by their abrading downward action and motioncreate a constant resistance. In all cases the slideways 17 should be soproportioned that their surplus material to be abraded by the stopclampsshall enable the production of the constant retarding resistance whichwill socure the uniformly-decreasing motion of the elelvator-car untilthe latter comes to a standsti l.

The present invention is intended only as an emergency-brake and mayonly come into IIO ' curve, and thereby prevent the dogs 14 fromengaging the stop-clamps 16.

It is evident that the movable dogs 14 and curve 21 will be dispensedwith whenever the car in its ordinary course does not pass below thestop-clamps 16, but always stop, ex-

cept in case of accident, before the car could strike the stop-clamps.In this latter arrangement a permanent projecting arm or other rigidstructure of the frame of the car placed to contact with the stop-clamps16 in case of accident would take the place of the special dog 14 shown.In other words, under the conditions just cited the car would employ afixed dog 14 to engage the stop-clamp instead of a movable dog 14, sincethe movable feature of the dog 14 is only useful when the car in itsusual course of travel is obliged to pass by the stop-clamps 16.

A great advantage derived from suspending the slideways 17 from a pointof the elevator well'or shaft and leaving them free on all sides to beacted upon by the clamps, as well on the face as on the back, is thatthis arrangement keeps the slideways in line for direct tension andtakes up the least space between the car and elevator-shaft. Theslideways 17 may be easily replaced by newiones whenever in case of anaccident a sufficient length of their surfacehas been abraded by thestop-clamps 16.

It is one of the purposes of the present invention, as above explained,to secure a constant retarding resistance which will produce auniformly-decreasing motion of the elevator-car until the latter comesto a standstill, and I have found that an abrading cut of one inch inwidth and from one-eighth to onequarter of an inch in depth inyellow-pine slideways ofiers a constant resistance against abrasion ofabout one thousand pounds. With this example of resistance given it isan easy matter to calculate the total aggregate width of the abradin gcut of all of the slideways for a given height of fall.

WVhat I claim as my invention, and desire to secure by Letters Patent,is

1. The combination with an elevator-car having a projecting part, of anelevator-shaft in which said car moves, slideways supported in tensionby said elevator-shaft, and the normally stationary clamps on saidslideways to be engaged by said projecting part of the car structure,the portion of the slideways'below said clamps being proportioned toresist the motion of the clamps and the latter being slidable byabrading the slideways, as described.

2. The combination of an elevator-car having movable dogs with anelevator-shaft in which said car moves, slideways supported in tensionby said elevator-shaft, clamps normally stationary on said slideways andin the path of the movable dogs but slidable by abrasion on saidslideways, and means to keep the dogs from striking the stop-clamps whenthe car travels at a safe speed, as described.

3. The combination of an elevator-car having movable dogs, with anelevator-shaft in which said ,car moves, slideways supported in tensionby said elevator-shaft, stop-clamps normally stationary on saidslideways, and in the path of the movable dogs, but slidable by abrasionon said slideways, means for keeping the dogs from striking said clampswhen the car travels at a safe speed, and a compulsory trackformaintaining said dogs in a normally outward position, as described.

4. The elevator-car, the movable dogs carried thereby, and mechanism foroperating said dogs,combined with suspended slideways located in theelevator-shaft and arranged in pairs, and the stop-clamps encompassingsaid slideways and normally stationary thereon,

the inner surfaces of said clamps being serrated and said slidewaysbelow the normal stationary position for said clamps being of greatercross-section than at said clamps; substantialy as set forth.

5. The elevator-car, the movable dogs carried thereby, the levermechanism for operating said dogs, and the stationary rail for saidlever mechanism, the said rail having anoutward curve at a definitepoint, combined with the suspended slideways in the elevator-shaft, andstop-clamps on said slideways and in the path of said dogs when thelatter are in their normal outward position, said slideways having agreater cross-section below than at said stop-clamps; substantially asset forth.

6. The car having a projecting arm, combined with a vertical slidewaysuspended in the elevator-shaft, and a stop-clamp on said slideway andnormally stationary thereon and in the path of said projecting arm;substantially as set forth.

In testimony that I claim the foregoing as my invention I have signed myname, in presence of two witnesses, this 18th day of October, 1897.

RUDOLPH 0. SMITH.

